Dissolution parameters of a solid product into a liquid solution, such as a liquid detergent used for cleaning and sanitizing, change based on the operating parameters of and inputs to the dissolution process. Spraying liquid onto a solid product to dissolve it into a liquid solution is one technique. With this technique, the operating parameters change in part based on characteristics within the dispenser, such as the distance between the solid product and the spray nozzle and the change in the pressure and temperature of the liquid being sprayed onto the solid product. Changes in a nozzle's flow rate, spray pattern, spray angle, and nozzle flow can also affect operating parameters, thereby affecting the chemistry, effectiveness, and efficiency of the concentration of the resulting liquid solution. In addition, dissolution of a solid product by spraying generally requires additional space within the dispenser for the nozzles spray pattern to develop and the basin to collect the dissolved product, which results in a larger dispenser.
Furthermore, varying characteristics of the liquid, such as temperature and pressure, may affect the concentration of the formed solution in a collection zone. If the temperature of the liquid rises, it has been shown that the higher temperature liquid will erode more of the solid product chemistry, which will result in a higher concentration level for the solution. This can be remedied by adding an additional liquid amount, or make-up liquid, to the formed solution in the collection zone. However, it can be difficult to correctly counteract the higher temperature liquid with an appropriate amount of liquid.
The pressure of the liquid can also cause problems for a dispensing system trying to obtain and maintain a solution within an acceptable concentration range. The pressure of the make-up liquid can cause more liquid to be introduced to the solution in the collection zone than is needed, which could reduce the concentration. The reduction in concentration could affect the sanitizing and other cleaning characteristics of the solution formed between the liquid and the solid product chemistry.
Therefore, there is a need in the art for a method and apparatus for continuously adjusting the amount of make-up liquid added to the formed solution in the collection zone by taking known relationships between the temperature of the liquid and the erosion rate of the solid product chemistry, and providing a method and apparatus that will continuously and variably adjust the amount of make-up liquid added to the solution in the collection zone based upon this known relationship. There is also a need in the art for a way to control the concentration of a solution independent of the pressure of the liquid introduced to the solution.